refactor(docker): 重构本地开发环境配置

将通用Dockerfile重命名为Dockerfile.php以明确用途
添加PostgreSQL自定义镜像配置以支持pgvector扩展
拆分数据库初始化脚本为mysql和postgres专用版本
更新docker-compose配置以使用新的构建文件

local/init_mysql.sql

@@ -0,0 +1,6 @@
+GRANT ALL PRIVILEGES ON *.* TO 'kennyyang'@'%';
+USE mysql;
+ALTER USER 'kennyyang'@'%' IDENTIFIED WITH mysql_native_password BY '!Ybw324!';
+ALTER USER 'root'@'localhost' IDENTIFIED WITH mysql_native_password BY '!Ybw324!' PASSWORD EXPIRE NEVER;
+ALTER USER 'root'@'%' IDENTIFIED WITH mysql_native_password BY '!Ybw324!' PASSWORD EXPIRE NEVER;
+FLUSH PRIVILEGES;